This PhD dissertation is about legal fictions in private law. A legal fiction, broadly, is a false assumption knowingly relied upon by the courts. The main aim of the dissertation is to formulate a test for which fictions should be accepted and which rejected. Subsidiary aims include a better understanding of the fiction as a device and of certain individual fictions, past and present. This research is undertaken, primarily, to establish a rigorous system for the treatment of fictions in English law - which is lacking. Secondarily, it is intended to settle some intractable disputes, which have plagued the scholarship. These theoretical debates have hindered progress on the practical matters which affect litigants in the real world. The dissertation is divided into four chapters. The first chapter is a historical study of common-law fictions. The conclusions drawn thereform are the foundation of the acceptance test for fictions. The second chapter deals with the theoretical problems surrounding the fiction. Chiefly, it seeks precisely to define 'legal fiction', a recurrent problem in the literature. A solution, in the form of a two-pronged definition, is proposed, adding an important element to the acceptance test. The third chapter analyses modern-day fictions and recommends retention or abolition for each fiction. In the fourth chapter, the findings hitherto are synthesised into a general acceptance test for fictions. This test, which is the thesis of this work, is presented as a flowchart. It is the author's hope that this project will raise awareness as to the merits and demerits of legal fictions, de-mystify the debate and bring about reform.

Bestämmelsen om tvångsinlösen i 22 kap. 1 § ABL är tvingande, vilket innebär att avsteg från vad som föreskrivs inte får göras genom bolagsordningen. Mot bakgrund av Högsta domstolens avgörande i NJA 2011 s. 429, synes bestämmelsens tvingande natur vara än mer vidsträckt. I förevarande fall ansågs nämligen ett aktieägaravtal, varigenom en majoritetsägare avstått från sin rätt att påkalla tvångsinlösen, sakna aktiebolagsrättslig relevans. Domstolen framhöll emellertid att sådana aktieägaravtal som huvudregel binder parterna. Författarna är av uppfattningen att blotta förekomsten av tvångsinlöseninstitutet utgör en inskränkning av principen om avtalsfrihet. Därutöver innebär Högsta domstolens avgörande att den välgrundade principen inskränks ytterligare. I förevarande uppsats utreds huruvida den sistnämnda inskränkningen är motiverad. Därutöver utreds även hur ett eventuellt avtalsbrott och en därtill inträdande skadeståndsskyldighet förhåller sig till det faktum att avtalsvillkoret saknar aktiebolagsrättslig relevans. Inledningsvis anser författarna att inskränkningen av avtalsfriheten som följer av NJA 2011 s. 429 är motiverad. Vidare har författarna konstaterat att skadeståndsskyldighet kan aktualiseras de lege lata eftersom parterna torde vara obligationsrättsligt bundna mot bakgrund av Högsta domstolens uttalande i NJA 2011 s. 429. Yttermera är författarna av uppfattningen att ett föreliggande skadeståndsansvar inte kan begränsas genom tillämpning av adekvansläran eller normskyddsläran. De lege ferenda anser författarna att ett aktieägaravtal som inskränker tvångsinlösenrätten inte bör tillerkännas obligationsrättslig verkan. Detta främst mot bakgrund av att det är en orimlig följd att ett avtal som inte kan göras gällande gentemot bolaget trots allt kan föranleda obligationsrättslig bundenhet och skadeståndsansvar. / The provision in chapter 22. 1 § of the Swedish companies act regarding compulsory purchases and sales of shares is imperative, meaning that derogations from the provision not is allowed through a company’s articles of association. The imperative nature of the provision has been further strengthened through the Swedish Supreme Court ruling NJA 2011 s. 429. In the mentioned case, a shareholders’ agreement in which a party has waived its right to claim a compulsory purchase, was found to lack affect in relation to the company. However, the court stressed that shareholders’ agreements, in principle, are valid and enforceable between the contractual parties, i.e. the shareholders. The authors’ opinion is that the mere existence of compulsory purchases and sales of shares constitute an infringement of the freedom of contract. Moreover, the mentioned court ruling entails an extension of the already existing infringement of this freedom. This thesis examines whether this, later infringement, is motivated. Furthermore, this thesis examines how a breach of a shareholders’ agreement – and liability to pay damages – relates to the fact that the contractual term that has been breached lacks affect toward the company.  According to the authors, the infringement of the freedom of contract derived from the mentioned court ruling is motivated. Furthermore, the authors have concluded that liability to pay damages may arise de lege lata, due to the fact that the contractual parties ought to be bound by the shareholders’ agreement according to the mentioned court ruling. In the authors’ opinion, the methods used to limit liability are not capable of doing so in this case. The authors suggest, de lege ferenda, that a term of a shareholder’s agreement where a party refrains from his right to claim a compulsory purchase or sales of shares not shall be binding between the parties.